And now, tennis star Serena Williams has shown how status, talent, and success are no factor in developing postpartum depression, and how it can affect anyone.

"Last week was not easy for me," she wrote in posts on Instagram and Twitter. "Not only was I accepting some tough personal stuff, but I just was in a funk. Mostly, I felt like I was not a good mom."

Williams has won 23 grand slams, arguably making her the most successful female tennis player of all time. But last week, she suffered the most catastrophic defeat of her career against Britain's Johanna Konta at the the Mubadala Silicon Valley Classic. She lost in straight sets in just 52 minutes.

In her post, she said her concerns about being a mother have been affecting her performance.

"I read several articles that said postpartum emotions can last up to 3 years if not dealt with," she wrote. "I like communication best. Talking things through with my mom, my sisters, my friends let me know that my feelings are totally normal. It's totally normal to feel like I'm not doing enough for my baby."

Williams has opened up about her struggles with motherhood before, notably in an article for CNN, where she described how she nearly died while giving birth to her daughter Olympia. Because of her medical history with pulmonary embolism, a condition where one or more arteries in the lungs become blocked by blood clots, she said she was lucky to survive the problems that occurred.

"First my C-section wound popped open due to the intense coughing I endured as a result of the embolism," she wrote. "I returned to surgery, where the doctors found a large hematoma, a swelling of clotted blood, in my abdomen. And then I returned to the operating room for a procedure that prevents clots from traveling to my lungs."

Despite her difficulties, Williams barely missed a beat, and returned to tennis earlier this year to secure a place in the Wimbledon final.

"I work a lot, I train, and I'm trying to be the best athlete I can be," Williams wrote in her post.

"However, that means although I have been with her every day of her life, I'm not around as much as I would like to be. Most of you moms deal with the same thing. Whether stay-at-home or working, finding that balance with kids is a true art. You are the true heroes. I'm here to say: if you are having a rough day or week — it's ok — I am, too!!!"

Messages of support, gratitude, and admiration have come flooding in from fans and fellow celebrities on social media, including a tweet from former tennis star Andy Roddick.